The indicated circuit uses an unusual buffer from National Semiconductor. The frequency is given by resistors R1 and R2 as well as capacitors C1 and C2.
This S-meter or signal strength meter, was originally designed for the 80's Regency receiver, but can...
This circuit is intended to reduce the 12V from a car outlet to 9V. The current is in the order of a...
This sensitive millivoltmeter for alternating voltages was found in a French publication in 1996...